Answer:
A
Explanation:
A is the only option.
Where are the other ones?
Mutations are harmful because any change in DNA can change a lot
Http://www.livescience.com/22537-skeletal-system.html
Are there choices to choose from, because that is a very general question?
Bacteria, archaea, plants, protists, animals, and fungi, can use cellular respiration.
And the main ones that use celluar respiration are autotrophs and heterotrophs.
Hope I helped you out (:
